The Hobbywing QuicRun 3660SL G2 Sensorless Brushless Motor is designed to deliver extreme power with higer efficiency This dust-proof motor for will be a great option for off-road vehicles and trucks. Hobbywing has designed a motor compatible with a wide range of RC models. Package includes one brushless motor. Features: High efficiency for more power with lower temperatures! 4-pole rotor design for more torque with strong explosive force Compared with the previous generation of motors, the output power and efficiency are increased by more than 10%, and the motor temperature is effectively reduced under the same load. 0.2mm thick silicon steel laminations, high strength explosion-proof rotor, high-temperature resistant coil, and imported high-precision and high-quality bearings make the motor super durable. Specifications: Input Voltage: 2-3S LiPo KV: 3700kV Pole: 4 Motor Diameter: 1.42" (36mm) Motor Length: 2.36" (60mm) Shaft Diameter: 0.20" (5mm) Shaft Length: 0.73" (18.5mm) Front Bearing size: D16*D5*T5 Rear Bearing size: D13*D5*T4 Weight: 278g